Good to see you. It's been a while. Nice to hear you've kept working on digital photomanipulation.
There are several ways to get that "Godfather" style image. We'll cover a few.
1. First of all, you are going to need to mask your character to seperate him from the background. Picking a good source image will be important. Images that have a lot of contrast already (wide changes between light and dark parts of the images) will lend themselves to better results using this technique. Image: http://static.guim.co.uk/sys-images/BOOKS/Pix/pictures/2012/2/22/1329910745597/The-Godfather-007.jpg
2. Place that render on a black background.
3. This is where things can get a little complicated. The following image has the brightness and contrast changed. Image: http://www.thenoobnews.com/uploads/2012/03/godfather.jpg width= 400
So using Paint.net, go to Adjustments>Brightness/Contrast
. Take the contrast all the way to 100. You should be left with a black and white image. Now, change the brightness. You are going to have to play with this to get it right.
Now, if you want the image only monochrome (black and white), you are probably going to have to some tracing. This is where it can get difficult. It may be tracing but it's a lot like drawing. This is where vector art usually starts.
The result can be something like this: Image: http://samaita.com/vectoor/wp-content/uploads/2012/03/Vectoor-Don-Vito-Corleone.jpg
(not my work, found using Google images)
This particular image used a type of vector trace but you can still see where it was cleaned up by hand. These can be very labor intensive depending on how detailed you want to get.